1. Field of the Invention
The present invention relates to a lens-fitted photographic film package and more particularly to a lens-fitted photographic film package which is improved as to its suitability for the operations of disassembling, inspecting and reassembling the reusable parts of the package. The present invention also relates to a lens-fitted photographic film package with a built-in flash unit, which is improved as to its compactness.
2. Related Art
Lens-fitted photographic film packages (hereinafter simply referred to as film packages) are well known, having a simple photograph-taking mechanism as disclosed in U.S. Pat. No. 4,884,087. Such film packages can be purchased nearly everywhere at low prices, making it possible to take photographs anywhere without carrying about heavy and expensive cameras.
Such a film package has a film housing equipped with a taking lens and containing a 135-type photographic film cassette that has been drawn out of the photographic film cassette and wound in a roll.
A film package with a built-in flash unit is also well-known in the art. FIG. 10 of the accompanying drawings shows a film housing 90 of such a conventional film package having a built-in flash unit 91. The flash unit 91 is attached to a main body 92 on the same side as a film supply chamber 93 containing a film roll drawn out from a film cassette 94. A photograph-taking unit 95 including a taking lens, a shutter mechanism and a film advance stop mechanism for advancing the film one frame at a time, is also attached to the main body 92 at the front middle portion thereof. Thereafter, a front cover 96 is attached to the main body 92 to cover the front and top sides of the main body 92. A rear cover 98 is attached to the rear side of the main body 92 so as to close the film supply chamber 93 and a film take-up chamber 97 to contain the film roll and the film cassette 94 in a light-tight fashion. The flash unit 91 consists of a light emitting portion 100, an electric circuit including a capacitor 101, and a printed circuit board 102 on which the light emitting portion 100 and the electric circuit are mounted.
The printed circuit board 102 is secured to the main body 92 through engagement between a hole 102a through the board 102 and a hook 92a on the main body 92. The light emitting portion 100 and the capacitor 101 are disposed above the film supply chamber 93. A flash charging switch 103 is integrally formed with the front cover 96, and a metal contact blade 104 is mounted on the back of the flash charging switch 103. When the switch 103 is depressed, a pair of conductive surfaces 105 formed on the printed circuit board 102 are connected to each other through the contact blade 104, to charge the capacitor 101. The capacitor 101 is discharged to cause the light emitting portion 100 to emit a flash of light in response to a shutter release operation.
Because the film package cannot be repeatedly loaded with film, after the exposure of all the available frames of the contained film, the whole film package is forwarded to a photofinisher. The photofinisher removes the exposed film from the film housing and subjects it to a photographic printing process, in the same manner as other 135-type films. The obtained photoprints and the developed film are returned to the customer.
The thickness of the film unit is only slightly greater than the diameter of the photographic film cassette, so as to render the film package more readily portable. However, there have been carried out studies to make the size of compact cameras approach the size of a credit card or a cigarette case. In this connection, it is desired to further miniaturize the film package whilst still using a 135-type photographic film cassette.
There is disclosed a much more compact film package with a 135-type photographic film cassette and a built-in flash unit in U.S. patent application Ser. No. 07/928,703. In this film package, a portion of the front cover has a curve complementary to the front outside surface of the film take-up chamber containing the film cassette thereby to serve as a grip, while the other portion of the front cover is made flat and disposed rearward relative to the grip portion by forming the film supply chamber smaller in diameter than the film take-up chamber. However, if the flash unit is disposed in front of the film supply chamber, it is difficult to remarkably reduce the thickness of a film package with such a flash unit.
Meanwhile, in the interest of environmental protection or the reduction of industrial waste, the modern trend in industry is toward recycling. For this purpose, and also to save money, the used film packages are recovered from the photofinishers, and disassembled and inspected by the manufacturer, and reused in new film packages or melted for use as raw materials. To this end, film packages suitable for reuse have recently been proposed. For example, a film package having a photograph-taking unit which is adapted to be reused in a new film package, is disclosed in U.S. patent application Ser. No. 07/913,435.
In this earlier film package, a cylindrical lens holder for holding the taking lens elements is formed on a front portion of the photo-taking unit, and the lens elements inserted in the lens holder are fixedly held between the lens holder and the front cover when the front cover is attached to the main body. When disassembling the above film package for reuse of the photo-taking unit, the taking lens elements tend to drop out of the lens holder after the front cover is detached from the main body. Therefore, this film package is unsuitable for automatic disassembling and reassembling operations.
Moreover, although the photo-taking unit disclosed in the last mentioned U.S. application makes it possible to test the performance of the mechanism of the unit independently from other parts without the need for mounting the unit on the main body, it is nevertheless impossible to check the transparency, the eccentricity and other properties of the taking lens system of this unit unless the unit is mounted on the main body and covered by the front cover. Therefore, the known photo-taking unit needs a large and complicated lens inspection system.
Meanwhile, film packages with a viewfinder optical system are also known, for example from Japanese Laid-open Utility Model Application No. 3-114829. The viewfinder optical system disclosed in this application is held in a lens barrel which is secured to the main body. In another type of such film package, the viewfinder optical system is disposed in a lens holding recess which is formed integrally with the top wall of the front cover, and a pressing plate is removably fitted over the recess to hold the viewfinder optical system immovable therein.
Although the film housing is encased in an outer casing from the time of shipment from the factory until the time of processing the exposed film, the front cover is partly exposed to the outside, i.e., in the region of the shutter button, the lens hood and so forth. Therefore, these exposed portions of the front cover may often be stained or scratched, so that the front covers of the recovered film packages are mostly melted to be recycled as raw material. In the case of a front cover having a viewfinder optical system mounted therein, it is necessary, before melting the front cover, to remove the pressing plate and the viewfinder optical system therefrom. But this increases the number of operations necessary for recycling the film packages.